Method:
Soak the tapioca in about 250ml cold water for about 10 minutes. It should swell and absorb all the water. Coarsely mash the potatoes, chillies, salt, peanuts, if using, and coriander together. Mix in the tapioca. Heat the oil in a frying pan. To check that the oil is hot enough, drop a small piece of the potato mixture into the oil: if it sizzles, the oil is ready.

With wet hands, roll the potato mixture into spheres the size of a golf ball, then flatten the balls to make patties. Depending on the size of the fryer, place a few patties at a time in the oil. Fry on one side for 2 minutes, then turn them over and fry for another 2 minutes until golden brown. Remove with a slotted spoon and drain them on kitchen paper.